MUTCD R3-15a: Preferential Lane Advance Signs

The R3-15a sign is covered in Section 2G.06 of the Manual on Uniform Traffic Control Devices, 11th Edition. Below are the provisions from that section that describe when the sign is used and how it is placed.

What it means and when it is used

• Guidance · Recommended (should)
  The Preferential Lane Advance (R3-12, R3-12f, R3-15, and R3-15d) signs (see Figure 2G-1 ) should be used for advance notification of a barrier-separated, buffer-separated, or contiguous preferential lane that is added to the general-purpose lanes (see Figure 2G-2 ).
• Guidance · Recommended (should)
  The Preferential Lane Advance (R3-12e and R3-15a) signs (see Figure 2G-1 ) should be used for advance notification of a general-purpose lane that becomes a preferential lane (see Figure 2G-3 ).

Placement and mounting

• Guidance · Recommended (should)
  On conventional roads, for general-purpose lanes that become preferential lanes, a post-mounted (R3-12e) or overhead (R3-15a) Preferential Lane Advance sign should be installed in advance of the beginning of or initial entry point to the preferential lane at a distance determined by engineering judgment based on speed, traffic characteristics, and other site-specific considerations. The distance selected should…
• Guidance · Recommended (should)
  On freeways and expressways, for general-purpose lanes that become preferential lanes, an overhead Preferential Lane Advance (R3-15a) sign should be installed at least 1 mile in advance of the beginning of the preferential lane restriction.
• Option · Permitted (may)
  Additional post-mounted or overhead Preferential Lane Advance signs may be placed farther in advance of or closer to the beginning or initial entry points to a preferential lane.

Where to read the rest

• Full text: MUTCD Section 2G.06: Preferential Lane Advance Signs
• Mounting height, lateral offset and retroreflectivity for any sign: MUTCD sign placement guide

Related signs in Section 2G.06